Considered by some[[note]]See the YMMV about ''Literature/OperationMassacre'' about this[[/note]] to be the TropeCodifier for [[NonFictionLiterature the Non-Fiction Novel]], ''In Cold Blood'' was written by Truman Capote and published in 1966.

It tells the story of Perry Smith and Richard Hickock, two recently-paroled convicts in Kansas. One day in 1959, they hear from a fellow con named Floyd Wells about a farmer he worked for named Herb Clutter. According to Wells, Clutter kept a safe in his house with lots of cash inside. So, the two decide to rob the place, LeaveNoWitnesses and head for Mexico with the cash. And that's what they do. Except for one small thing: there was no safe.

Capote originally started the book as an article on the massacre. He was able to interview both Smith and Hickock for the project shortly after their arrest. The huge amount of info he got led him to change course during development.

''In Cold Blood'' was adapted into a well-regarded 1967 film directed by Richard Brooks, starring Robert Blake as Smith and Scott Wilson as Hickock. It was also made into a TV miniseries in 1996 starring Anthony Edwards as Hickock and Eric Roberts as Smith. The [[MakingTheMasterpiece story of its creation]] was [[DuelingMovies told twice within a year]]: first as ''Film/{{Capote}}'' in 2005, and then as ''Infamous'' in 2006.

!!This work contains examples of:

* AbusiveParents: Perry's mother had a severe case of alcoholism and a tendency to bring home men whom she had sex with right in front of her children. Perry's father would have killed him if the shotgun hadn't misfired.
* AdultFear: In spades. Strangers have broken into your house, have captured and bound your family, and are about to rape your daughter... and there's not a thing you can do about it.
* AffablyEvil: While Smith is twitchy with barely suppressed rage, Hickok is a cheerful, affable murderer.
* AttemptedRape: Dick is beginning to come on to Nancy Clutter during the home invasion, but Perry prevents it from going any further.
* CallBack: In the film, Perry tells about his rather odd fantasy of a giant yellow bird saving him from the abusive nuns at his school. When they're getting arrested, Dick says "Hey, Buddy, put in a call for that big, ol' Yellow Bird!"
* DeathRow: Hickock and Smith find themselves in here after they're convicted of the Clutter murders.
* DeliberatelyMonochrome: By 1967, when most movies were being made in color, making this one in black and white was a deliberate artistic choice.
* {{Ephebophile}}: Dick Hickock. Perry even speculates that Nancy was "probably the real reason" he chose The Clutter Farm for the robbery.
** Later in the book he attempts to seduce a 12 year old girl on the beach, until Perry steps in.
* {{Epigraph}}: An excerpt from ''La Ballade des Pendus'' (the Ballad of the Hanged) by François Villon.
* EvenEvilHasLovedOnes: Hickock's sole regret out of the entire Clutter affair seems to be how it's harmed his mother and father, who he thinks brought him up fine and never treated him wrong in his life.
* EvenEvilHasStandards: Smith may be a mass-murderer, but he's disgusted by Hickock's attempt to rape Nancy Clutter during the home invasion.
* FaceDeathWithDignity: Dick Hickock greets his captors and mounts the scaffold with grim dignity, never betraying any fear or despair.
* {{Flashback}}: A flashback in the film to Smith as a child, with his family at the rodeo.
* ForegoneConclusion: Clutter and his family are killed.
* ForWantOfANail: The daughter's friend turning down her invitation to spend the night undoubtedly saved her life.
* GoryDiscretionShot: The Clutter daughter turns out her lamp. . .and the next thing we see are their friends arriving to pick them up for church. All we hear is one of them screaming upon discovering the bodies.
** Even when it flashes back to the murders, we hear the gunshots, but never see the results.
** ''Completely'' averted with the execution of the second killer.
* GrayRainOfDepression: Rain hitting the window in the movie as Perry Smith sums up his sad life.
* ImagineSpot: Perry, a would-be guitarist and singer, imagines himself playing a Las Vegas show.
* InstantMysteryJustDeleteScene: It starts with the killers arriving at the Clutter farmhouse, and then goes to the aftermath. It goes back in time to explain why it happened.
* KickTheDog: Or more accurately, [[KickTheDog Run Over The Dog.]] While in Mexico, Dick sees an emaciated dog and runs over it with his car. He claims that it's a MercyKill, but his extremely apparent glee and excitement about it afterwards belies [[TheSociopath his true mental state.]]
* KnowNothingKnowItAll: While on DeathRow, Hickock considers Smith to be this. Despite Smith's "million dollar words", Hickock claims that he's just as dimwitted as himself. He further claims that Smith despises the other mass-murdering inmate, Lowell Lee Andrews, because Andrews actually had an education at the University of Kansas and makes Smith look stupid by comparison.
* LeaveNoWitnesses: Dick repeatedly says that there needs to be "no witnesses" after they rob the Clutters, fearing that they might testify against them if they're caught. This is what leads to the Clutters' deaths and the resulting fallout.
* MatchCut: Several in the movie, as when Perry tossing a cigarette off a bridge is followed up by the cops dropping a magnet over a bridge in an attempt to find the murder weapons.
* MoralMyopia: Both Smith and Hickock feel they are treated unjustly by the townsfolk and the prosecution during the trial, but neither expresses any regret about killing the Clutters.
* NoDeadBodyPoops: Averted. One of the killers begs to be allowed to use the bathroom before his hanging because he doesn't want this to happen. His executioners tell him it's going to happen anyway--"They all do it."
* OhCrap: When Dewey shows Dick [[spoiler: the bloody footprint and matching boot]], he knows the jig is up.
* ThePerfectCrime: In Hickock's words, they thought their plan would be "a cinch, the perfect score."
* PetTheDog: The two killers genuinely bond with the little boy and his grandfather who they pick up, stopping to gather bottles, singing with him, and even fairly splitting the profits from the bottle collection.
* PoliticallyIncorrectVillain: Both Hickock and Smith frequently call African-Americans "niggers", and once refer to a Chinese restaurant as a "Chink restaurant".
* PrecisionFStrike: The relaxing of censorship standards by 1967 with the death of UsefulNotes/TheHaysCode led to this being the first American film to use the word "bullshit".
* RapeIsASpecialKindOfEvil: Perry Smith has nothing but distaste for Dick when he tries to rape Nancy Clutter.
* TheReasonYouSuckSpeech: Dick gives a very blunt and cruel one to Perry in Mexico. He shatters Perry's fantasy of their "quest" to find lost Spanish Gold from some silly phony "treasure maps" and tells him to grow up.
** Also serves as a bit of a WhamLine: there IS no "plan," and no prospects to get them out of their current predicament (broke, wandering, homeless and wanted by the law).
* TheRemake: The film was remade in 1996 as a TV Movie, which was far more faithful to the book.
* ShownTheirWork: The film was shot at the actual locations, including the actual Clutter house. The pictures on the walls are of the real Clutters.
* SpannerInTheWorks: When hitchhiking through America, Dick and Perry find themselves in the car with a lone salesman going to Omaha. Just as they're about to rob and kill the man, he pulls over for a black hitchhiker, forcing them to continue acting congenial for the rest of their ride and sparing the salesman's life.
* TemptingFate: Hickok, in the tradition of all dumb Vegas gamblers, proposes to Smith that they gamble their last $5 into a stake that will get them out of town. He says "I feel real lucky tonight." ''Immediately'' after those words escape his lips, they're pulled over by a cop, which eventually results in them being arrested for the Clutter murders.
* TrueCrime: Credited with establishing the modern form of the Genre.
* UnwittingInstigatorOfDoom: Floyd Wells. It all wouldn't have happened if he had kept his mouth shut about the safe.
* VillainsDyingGrace: When he knows he and Dick are cooked, Smith changes his confession to include the fact that he murdered all the Clutters, not Dick. This is mostly done because he thinks Dick's parents are good people that shouldn't have to live with the fact that their son is a killer.
* VillainousRescue: Smith saves Nancy Clutter from being raped by Hickock. Turns out to be [[SubvertedTrope subverted]], however, when Smith eventually kills Nancy like the rest of her family.